In the process of producing a semiconductor device such as IC and LSI, microfabrication by lithography using a photoresist composition has been conventionally performed. Recently, with the increase in integration degree of an integrated circuit, formation of an ultrafine pattern in the sub-micron or quarter-micron region is required. To cope with this requirement, the exposure wavelength also tends to become shorter, for example, from g line to i line or further to KrF excimer laser light. At present, other than the excimer laser light, development of lithography using electron beam, X-ray or EUV light is also proceeding.
The lithography using electron beam, X-ray or EUV light is positioned as a next-generation or next-next-generation pattern formation technology and a high-contrast, high-sensitivity and high-resolution resist composition is being demanded.
Particularly, in order to shorten the wafer processing time, elevation of sensitivity is very important, but when higher sensitivity is pursued, the pattern profile or the resolution indicated by the limiting resolution line width is deteriorated, and development of a resist composition simultaneously satisfying these properties is strongly demanded.
As one method to solve such a problem, a resist composition containing a specific basic compound is disclosed in for example, JP-A-2011-150282 (the term “JP-A” as used herein means an “unexamined published Japanese patent application”), JP-A-2012-48187 and JP-A-9-127700.